Elevated Geomagnetic Storm Activity Expected
Geomagnetic storm conditions are expected to increase over the next 24 hours with the arrival of an Earth-directed coronal mass ejection (CME). The CME was triggered by a long-duration X1.9 Solar Flare on Sunday 18 January at around 20:00 South African Standard Time (SAST).
Solar Flare
A Solar Flare is a sudden burst of light from the Sun with an immediate impact on the Earth’s day side, disrupting high-frequency radio communications. Solar Flares are ranked in five categories — A, B, C, M and X — based on their intensity. A-class flares are the weakest, while X-class flares are the most energetic. The African region was not affected by the high-frequency radio blackout on Sunday as it was observed during nighttime, mostly out of the flare’s impact range.
Image 1: The long-duration X1.9 Solar Flare on Sunday 18 January at 18:09 UT (20:09 SAST) from AR4341.
Image 2: On Sunday, the X-class flare caused high-frequency radio disruptions over the Pacific region.
Geomagnetic Storm
The Solar Flare triggered a Coronal Mass Ejection (CME) which is a cloud of plasma released from the sun. This CME is Earth-directed, currently travelling from the Sun to the Earth and expected to impact Earth from the early hours of Wednesday 20 January. This impact will interact with the Earth’s magnetic field and cause a geomagnetic storm. The geomagnetic storm could reach G4/Severe storm conditions.
The G-scale, used by space weather centres globally, categorises geomagnetic storms based on their intensity and potential impact. It ranges from G1 (minor), G2 (moderate), G3 (strong), G4 (severe) and G5 (extreme).
Forecast and Impact of the Geomagnetic Storm
The SANSA Space Weather Centre expect geomagnetic conditions to increase over the next 24 hours:
Expected: G1/Minor to G2/Moderate storms (Kp 5-6)
Likely: G3/Strong storm (Kp 7)
**Possible:**G4/ Severe storm interval (Kp 8)
Unlike terrestrial storms, geomagnetic storms largely go unnoticed by people because their effects are felt mainly through technological systems. Navigation, communication, and electricity networks are the most at risk. Industries such as aviation and drone operations can be affected by the impact on navigation systems and should take note of the K-Index, a standardised, global measure (0-9) of geomagnetic activity, showing how much the Earth’s magnetic field is disturbed.
SANSA operates a local K-Index from SANSA Hermanus and can be tracked at spaceweather.sansa.org.za.
Monitoring and Tracking space weather
SANSA monitors space weather through its operational 24/7 Space Weather Centre at SANSA in Hermanus, Western Cape and use a network of ground-based instruments over the African continent, the Southern Ocean and Antarctica. SANSA works with space weather centres across the globe to monitor these storms and is accredited by the International Civil Aviation Authority (ICAO) as a regional centre.
SANSA will be updating information throughout the storm period on this post.
For more information on space weather training and monitoring, contact SANSA at This email address is being protected from spambots. You need JavaScript enabled to view it.
